I'd love to mod an old Amiga or Apple IIc case with a mini-ITX board except there are two problems:

How do you get the original keyboard to work with a PS/2 or USB interface? Simply put, I don't have the electronics know-how and think that these half-done mods where you use an external keyboard are silly.

How can you do it without damaging the case? These are vintage computers, and while it is cool to have the vintage look it ain't cool to destroy a vintage computer for the sake of the mod. So it must be possible to restore the original machine.

AROS is an interesting project. I'm just waiting to see if anything comes of it. (And, for some reason, running the GNU toolchain has always struck me as very un-Amiga.)